1. Field of the Invention
The present invention relates to the configuration of a developer holding apparatus attached to a developing apparatus. The developing apparatus is used in an image forming apparatus in which an electrostatic latent image is formed on an electrostatic latent image bearing body and is developed into a visible image.
2. Description of the Related Art
An electrophotographic image forming apparatus performs an electrophotographic image forming process: charging, exposing, developing, transferring, and fixing. An electrostatic latent image is formed on the charged surface of a photoconductive drum, and is then developed with toner into a toner image. The toner image is transferred onto print paper. The toner image is then fused into the print paper. The amount of toner in a developing unit decreases as printing is performed. Some image forming apparatuses are configured such that the toner cartridge may be replaced with a new, unused toner cartridge when the toner in the toner cartridge has been exhausted. The toner cartridge has a toner discharging opening formed therein. The toner cartridge is mounted to the developing unit, and then a shutter is opened to allow the toner to be discharged from the toner cartridge into a toner reservoir of the developing unit.
The toner may adhere to the inner surfaces of the walls of the toner cartridge or remain deposited on the bottom of the toner cartridge. Some toner cartridges include a toner agitator that agitates the toner during developing, thereby minimizing the amount of toner remaining unused in the toner cartridge. Other toner cartridges include a toner agitator and a resilient film attached to the toner agitator or the inner walls of the toner agitator, thereby further reducing the amount of toner that remains unused in the toner cartridge.
Still other cartridges include a bar-shaped toner agitator to which a resilient film is attached. The resilient film scrapes the inner walls of the toner cartridge to scrape the toner remaining unused on the inner walls. Conventional toner cartridges tend to impair print quality.